From 90fb46a131e8f06fe2cb5c7d0cc73f08247758e6 Mon Sep 17 00:00:00 2001
From: fabiojb <fabio.jose.bohnenberger@gmail.com>
Date: Sun, 9 May 2021 22:35:36 -0300
Subject: [PATCH] Reuse already allocated chars array instead of substring

---
 .../de/siegmar/logbackgelf/SimpleJsonEncoder.java  | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/main/java/de/siegmar/logbackgelf/SimpleJsonEncoder.java b/src/main/java/de/siegmar/logbackgelf/SimpleJsonEncoder.java
index 6fd5e29..ee7b4f1 100644
--- a/src/main/java/de/siegmar/logbackgelf/SimpleJsonEncoder.java
+++ b/src/main/java/de/siegmar/logbackgelf/SimpleJsonEncoder.java
@@ -109,7 +109,8 @@ private void appendKey(final String key) throws IOException {
     private void escapeString(final String str) throws IOException {
         int currentIndex = 0;
         int lastCopyIndex = 0;
-        for (final char ch : str.toCharArray()) {
+        char[] chars = str.toCharArray();
+        for (final char ch : chars) {
             String escaped = null;
             switch (ch) {
                 case QUOTE:
@@ -132,19 +133,20 @@ private void escapeString(final String str) throws IOException {
                 case '\t':
                     escaped = "\\t";
                     break;
-            }
-            if (ch < ' ') {
-                escaped = escapeCharacter(ch);
+                default:
+                    if (ch < ' ') {
+                        escaped = escapeCharacter(ch);
+                    }
             }
             if (escaped != null) {
-                writer.append(str.substring(lastCopyIndex, currentIndex));
+                writer.write(chars, lastCopyIndex, currentIndex - lastCopyIndex);
                 writer.append(escaped);
                 lastCopyIndex = currentIndex + 1;
             }
             currentIndex++;
         }
         if (lastCopyIndex != currentIndex) {
-            writer.append(str.substring(lastCopyIndex));
+            writer.write(chars, lastCopyIndex, chars.length - lastCopyIndex);
         }
     }